Date:   Tue, 11 Jan 2022 05:04:06 +0100
From:   Willy Tarreau <w@1wt.eu>
To:     "Theodore Ts'o" <tytso@mit.edu>
Cc:     Andy Lutomirski <luto@kernel.org>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Marcelo Henrique Cerri <marcelo.cerri@canonical.com>,
        Simo Sorce <simo@redhat.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jeffrey Walton <noloader@gmail.com>,
        Stephan Mueller <smueller@chronox.de>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        Nicolai Stange <nstange@suse.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Arnd Bergmann <arnd@arndb.de>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        "Alexander E. Patrakov" <patrakov@gmail.com>,
        "Ahmed S. Darwish" <darwish.07@gmail.com>,
        Matthew Garrett <mjg59@srcf.ucam.org>,
        Vito Caputo <vcaputo@pengaru.com>,
        Andreas Dilger <adilger.kernel@dilger.ca>,
        Jan Kara <jack@suse.cz>, Ray Strode <rstrode@redhat.com>,
        William Jon McCann <mccann@jhu.edu>,
        zhangjs <zachary@baishancloud.com>,
        Florian Weimer <fweimer@redhat.com>,
        Lennart Poettering <mzxreary@0pointer.de>,
        Peter Matthias <matthias.peter@bsi.bund.de>,
        Neil Horman <nhorman@redhat.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Julia Lawall <julia.lawall@inria.fr>,
        Dan Carpenter <dan.carpenter@oracle.com>,
        Andy Lavr <andy.lavr@gmail.com>,
        Petr Tesarik <ptesarik@suse.cz>,
        John Haxby <john.haxby@oracle.com>,
        Alexander Lobakin <alobakin@mailbox.org>,
        Jirka Hladky <jhladky@redhat.com>,
        Eric Biggers <ebiggers@kernel.org>
Subject: Re: [PATCH v43 01/15] Linux Random Number Generator
Message-ID: <20220111040406.GB26248@1wt.eu>
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On Mon, Jan 10, 2022 at 10:10:15PM -0500, Theodore Ts'o wrote:
> If we must support this in the upstream kernel, then configure it via
> CONFIG_RANDOM_SECURITY_THEATRE which redirects getrandom(2) and
> /dev/[u]random to DRBG.  I'd prefer that it be possible for someone to
> put "random_security_theatre=0" on the boot command line which would
> disable redirecting the interfaces to DRBG so if it turns out that
> DRBG *is* less secure, we can give advice on how to turn it off
> without requiring a patched kernel.  :-)

In this case, why not do it the other way around ? Instead of having
yet-another config option, just indicate that fips-like randoms are
enabled at boot via "random_security_theatre=1". Distros have their
solution which can even be documented for their customers and that's
done. Nobody uses it by default, the name is discouraging enough, but
for those who know they want it, it's easy to turn it on, and at the
same time it delivers them the reminder about what all this really is.

Willy